

<script>
window.onload = function(){
	var docs = document.childNodes,
		html = docs[0],
		head = html.firstChild,
		body = html.lastChild;
	
	alert(head.innerHTML);//<script>....-->
	alert(body.innerHTML);//<div>A</div>
	alert(head.childNodes.length);//3			## TITLE/SCRIPT/!
	alert(head.childNodes[0].nodeName);
	
	alert("结论： SCRIPT和注释节点放在了head，最后出现的div放到了body");
}
</script>

<!--  注释的节  -->

<div>A</div>
